导演：大卫·杰克逊 David Jackson
Robin De Santis
卢卡斯·盖比尔 Lucas Grabeel
Marnie 和她弟弟准备上大学了。但这所学院是万圣节城大学，也被称为女巫大学。Marnie 因她的善举和她在前几部电影中的工作获得了全额奖学金。让她的母亲Gwen 感到很失望的是，Dylan不情愿地被Gwen 逼着去照看Marnie。然而，这所学校视乎并不是那样的。在学校里，女巫和男巫不能使用魔法，相反，他们学习莎士比亚和古老的魔法历史。Marnie 原以为她会学会如何使用魔法，现在她已经垂头丧气了。她遇到了她的老朋友Ethan (Lucas Grabeel 饰)，并结识了一个新的朋友精灵Aneesa (Summer Bishil 饰)。她还在Sinister 的姐妹中树了三个新敌人，就是Dylan 紧接就迷上的一群邪恶的女巫......
Marnie and her brother are ready to go to college. But the college is Halloweentown University also known as Witch University. Marnie is offered a full scholarship for her good deeds and for her work in the previous movies. Much to her mother, Gwen's, dismay she goes, with Dylan reluctantly forced along by Gwen, to keep an eye on Marnie. The school, however, is not what it seems. At the school witches and warlocks can't use magic, instead they learn about Shakespeare and old magic history. Marnie had thought she was going to learn how to use her magic and is now crestfallen. She runs into her old friend Ethan (Lucas Grabeel) and makes a new friend Aneesa the genie (Summer Bishil). She also makes three new enemies in the Sinister Sisters, a triad of malevolent witches with whom Dylan is immediately infatuated.
Sadly, Marnie discovers that she in fact is responsible for the restriction on the use of magic at the University. The University was originally established only for Warlocks and Witches to learn how to use magic, but when the portal was opened most of them went to college in the mortal realm. Because of that, Witch University had to let several different creatures come to the school so that the teachers would actually have students to teach. Since then the school has allowed mortals and other magical beings to attend. The classes are boring for Marnie until a box, with the name "S. Cromwell" inscribed on it, magically appears in front of her. Most people at the school believe that Marnie used her magic to conjure up the box, but it was brought to her by fate, and was therefore out of Marnie's control. Marnie meets with one of her professors, Miss Periwinkle, and asks for an explanation. Miss Periwinkle tells Marnie that the S. stands for Splendora, but not a word more about it is mentioned. Chancellor Goodwin tells Marnie that she believes that she did not conjure up the box, and that it was indeed fate which brought it to her.
Marnie and Dylan attempt to discover the secret of the box, and he reveals that he used magical speed reading at home to skip a grade. He uses it again secretly and learns that the box contains the Gift, though the Gift itself remains unknown to them. Meanwhile the Sinister sisters use Dylan's infatuation with them to make him do their homework for them.
Also in the shadows, a mysterious group known only as the Dominion, realizes that the Gift is near and tries to use Marnie to open the box. Marnie decides to go into the past to meet Splendora and learn about the true nature of the enigmatic gift. Splendora explains that the power of the Gift is the power to control anyone by force of will, a power that witches are forbidden to use. Marnie realizes that her principal and Dr. Grogg are in the Dominion and Splendora bestows upon her the key to the box containing the Gift. Also, Splendora is revealed to in fact be Marnie's grandmother Aggie. Agatha is her middle name and she hates the Splendora part so she eventually dropped it. Marnie returns to the present to open the box, but before she does, she creates the Halloweentown giant pumpkin for Splendora, telling her she'd need it. Surprisingly, stated by Splendora, Marvin, (Merlin's cousin), is Marnie's great-grandfather. This is given as a hint when Splendora tells Marnie, "...even King Arthur said that the whole royalty thing was harder than it looked."
Chancellor Goodwin steals the gift for the Dominion and the Sinisters, in order to use it to take over Halloweentown. Knowing that only a Cromwell can use the Gift, the Sinister Sisters (working with the Dominion) transform Dylan into a dog to compel Marnie to comply with their demands. If the Sinisters and the Dominion don't turn him back he will stay that way forever after Halloween passes. They agree to return him to his natural form if Marnie controls Halloweentown for them. While it seems that she has agreed to aid them in their heinous plot, she is really fooling them, and turns on them once her brother is released from the dog transformation spell. Together Marnie, Dylan and Gwen destroy the Gift with help from Aneesa, Marnie's genie friend. The Dominion, having been discovered for the evil ones that they are attempt an escape, but are betrayed by none other than Professor Periwinkle. Professor Periwinkle is revealed to be an undercover detective and apprehends the group.
The malevolent Sinister Sisters lose their powers, but Marnie learns that Ethan willingly gave his powers up. Marnie and Ethan begin a new relationship and leave on a date. The movie ends when Dylan discovers that Marnie didn't destroy The Gift, she left it for him in a book. And since spells cast on the grounds of Witch University become permanent at the stroke of midnight, The Gift belongs to him, the only person Marnie trusts with its power. Saving the power of The Gift for important uses only, he puts the book back, showing a glowing, red S at the end of the film.
Summer Bishil .... Aneesa
Katie Cockrell .... Sage Sinister
Kellie Cockrell .... Saphire Sinister
Robin De Santis .... Fairy
Darren Ewing .... Morose Cashier
卢卡斯·盖比尔 Lucas Grabeel .... Ethan Dalloway
Cheyenne Hall .... Vampire
Brighton Hertford .... Young Periwinkle
Judith Hoag .... Gwen Cromwell Piper
Millicent Martin .... Prof. Persimmon Periwinkle
Christopher Robin Miller .... Young Troll
萨拉·帕克斯顿 Sara Paxton .... Marnie Piper
戴比·雷诺兹 Debbie Reynolds .... Agatha Cromwell
Laura Summer .... Voice
Tisha Vaculin .... Cheerleader #1
Leslie Wing .... Dr. Goodwyn (as Leslie Wing-Pomeroy)
Eliza Wren .... Geeky Girl
Kristy Wu .... Scarlett Sinister
Dan Young .... Dr. Ichabod Grogg
Keone Young .... Silas Sinister